LSST Applications  21.0.0-142-gef555c1e+42c9bccae2,22.0.0+052faf71bd,22.0.0+1c4650f311,22.0.0+40ce427c77,22.0.0+5b6c068b1a,22.0.0+7589c3a021,22.0.0+81ed51be6d,22.0.1-1-g7d6de66+6cae67f2c6,22.0.1-1-g87000a6+314cd8b7ea,22.0.1-1-g8760c09+052faf71bd,22.0.1-1-g8e32f31+5b6c068b1a,22.0.1-10-g779eefa+a163f08322,22.0.1-12-g3bd7ecb+bbeacc25a9,22.0.1-15-g63cc0c1+2a7037787d,22.0.1-17-ge5a99e88+3d2c1afe2e,22.0.1-19-g88addfe+6cae67f2c6,22.0.1-2-g1cb3e5b+84de06d286,22.0.1-2-g8ef0a89+6cae67f2c6,22.0.1-2-g92698f7+1c4650f311,22.0.1-2-ga9b0f51+052faf71bd,22.0.1-2-gb66926d+5b6c068b1a,22.0.1-2-gcb770ba+0723a13595,22.0.1-2-ge470956+ff9f1dc8d5,22.0.1-22-g608e23ac+2ac85e833c,22.0.1-29-g184b6e44e+8b185d4e2d,22.0.1-3-g59f966b+11ba4df19d,22.0.1-3-g8c1d971+f90df4c6d0,22.0.1-3-g997b569+d69a7aa2f8,22.0.1-3-gaaec9c0+4d194bf81c,22.0.1-4-g1930a60+283d9d2f1a,22.0.1-4-g5b7b756+c1283a92b8,22.0.1-4-g8623105+6cae67f2c6,22.0.1-7-gba73697+283d9d2f1a,22.0.1-8-g47d23f5+43acea82f3,master-g5f2689bdc5+40ce427c77,w.2021.38
LSST Data Management Base Package
hashCombine.h
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5  * This product includes software developed by the
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22 #ifndef LSST_UTILS_HASH_COMBINE_H
23 #define LSST_UTILS_HASH_COMBINE_H
24 
25 #include <functional>
26 
27 namespace lsst {
28 namespace utils {
29 
35 inline std::size_t hashCombine(std::size_t seed) noexcept { return seed; }
36 
59 // This implementation is provided by Matteo Italia, https://stackoverflow.com/a/38140932/834250
60 // Algorithm described at https://stackoverflow.com/a/27952689
61 // WARNING: should not be inline or constexpr; it can cause instantiation-order problems with std::hash<T>
62 template <typename T, typename... Rest>
63 std::size_t hashCombine(std::size_t seed, const T& value, Rest... rest) noexcept {
64  std::hash<T> hasher;
65  seed ^= hasher(value) + 0x9e3779b9 + (seed << 6) + (seed >> 2);
66  return hashCombine(seed, rest...);
67 }
68 
90 // Note: not an overload of hashCombine to avoid ambiguity with hashCombine(size_t, T1, T2)
91 // WARNING: should not be inline or constexpr; it can cause instantiation-order problems with std::hash<T>
92 template <typename InputIterator>
93 std::size_t hashIterable(std::size_t seed, InputIterator begin, InputIterator end) noexcept {
94  std::size_t result = 0;
95  for (; begin != end; ++begin) {
96  result = hashCombine(result, *begin);
97  }
98  return result;
99 }
100 
101 }} // namespace lsst::utils
102 
103 #endif
py::object result
Definition: _schema.cc:429
int end
std::size_t hashIterable(std::size_t seed, InputIterator begin, InputIterator end) noexcept
Combine hashes in an iterable.
Definition: hashCombine.h:93
std::size_t hashCombine(std::size_t seed) noexcept
Combine hashes.
Definition: hashCombine.h:35
A base class for image defects.